Since the earliest days of automobiles, back then nostalgically reminiscing, referred to as “horseless carriages”, the driver in particular as well as the passengers struggled to see well in wet/muddy conditions.
Goggles soon became obstructed by flying debris. Later a windshield was provided and thereafter a wiper blade was invented to keep the windshield clear of raindrops and debris. Later on the vehicles came equipped with built-in windshield washer devices that could spray the windshield to assist in washing the bug splatter and other debris collected on to the windshield.
More recently, chemicals such as Rainx® have been developed that create a hydrophobic clear film on the windshield to make the raindrops disperse into small, very small droplets that rapidly are blown off the speeding vehicle, making the use of windshield wiper almost unnecessary at high speeds.
In the late 1990's, the Chevrolet Camaro introduced a low angle, curved windshield that similarly could rapidly expel water at very high speeds. As one can appreciate at speeds in excess of 80 miles per hour, the wiper blades have a tendency to be slow and the advantage of a windshield that remains clear at high speeds is a great advantage. This is true even if it is not wise to speed under such conditions. Nevertheless this high speed rain-free phenomenon would have tremendous value if it could be used at slower speeds.
Several prior art patents have proposed providing an air wiper for a vehicle which is capable of effectively blowing away rainwater: JP 06-156204; JP 61-110653 and RU 2004106253 all teach the use of an air compressor type device that expels air up onto a windshield in an attempt to create an air barrier to protect the windshield. U.S. Pat. No. 5,852,846 entitled “Windshield Airstream Deflector for Vehicles” similarly uses a multistage turbine in combination with an air flow duct to provide an air blanket to act as a shield to prevent rain, snow, sleet or freezing rain, insects or other airborne debris from accumulating on the windshield. In this prior art device the air flow can be heated to assist the wiper blades from becoming ice laden and ineffective in cold weather regions.
A similar concept is found in U.S. Pat. No. 5,001,966 entitled “Automobile Windscreen Cleaning System” that uses a foil coupled to a turbine or other high velocity, high pressure air source.
GB 2341787 entitled “Air Jet Windscreen Cleaners” has a turbine providing an air jet from the top of a windshield down or alternatively has a pair of wiper arms wherein the air jet flow causes what appears like conventional wiper blades to rise on a cushion of air and translate back and forth using air flow to clear the water.
All of these concepts clearly appreciate the value of air flow as a means to keep a windshield clean and every one has the air flow directed from under the hood or front bonnet to flow vertically upwardly or in case GB 2341787, vertically downwardly except when alternatively using the wipers semi-circular sweeping action.
These devices insure the airflow is uniformly covering the entire windshield with air flow and therefore appear to be a logical location for such air jets to be located. This, however, may not actually be the case for several reasons. A careful review of these prior art devices shows for the vertical flow path to result numerous small orifices or very long narrow slits have to be provided and in snowy, icy regions these jet openings can easily be blocked or frozen shut if covered by several inches of snow or a layer of ice. Ideally, to keep this from occurring the air must be heated in the winter to first de-ice itself and only then can the device function properly.
The present invention has a superior way of creating an air curtain or barrier across a windshield that can be achieved on each side of the windshield adjacent the pillars.
The present invention, while ideally suited for high pressure flows, can work very well with high volume lower pressure air flows by using a uniquely designed lateral flow device. This and other features of the invention are described in the following written description.